“In Search of the Best Clock” David W. Allan, Marc A. Weis, and Trudi K. Peppler Copyright © 1989 by The Institute of Electrical and Electronics Engineers. Reprinted from: IEEE Transactions on Instrumentation and Measurement Volume 38, No.2 April 1989 ISSN: 0018-9456 This material is posted here with permission of the IEEE. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution must be obtained from the IEEE by sending a blank email message to: pubspermissions@ieee.org. Subscriptions to IEEE Transactions on Instrumentation and Measurement can be obtained by contacting IEEE Customer Service: Phone: +1 800 678 IEEE [4333] (toll-free, USA and Canada only) or +1 732 981 0060 w Fax: +1 732 981 9667 w E-mail: customer-service@ieee.org w